1. Field of Invention
The present invention relates to a surface bonding fastener for opening and closing an opening of package, especially to a surface bonding fastener capable of efficiently preventing, while the package is reversely placed, contents contained in the package from unintentionally opening the opening of the package and then dropping out of the package.
2. Related Prior Art
The well-known surface bonding fastener applied for a package (e.g., a zipper bag) mainly uses plastic concave-convex strips respectively disposed near an opening of the package and extending in a transverse direction to achieve a purpose of repeatedly opening and closing the opening of the package. In this regard, however, while the package is reversely placed in the unintentional case or in the transporting process, contents contained in this package (especially for the contents having certain amounts of weight) will apply pressure to the surface bonding fastener which is used to close the opening of the package. Thus, the opening of the package has a possibility to be opened by such pressure, whereby there exists a risk for the contents contained in this package to be dropped out of the package.
FIGS. 1 and 2 show a surface bonding package applied for a package which has been proposed for solving the above-mentioned problems.
As shown in FIG. 1, such surface bonding package comprises a first base sheet 91 and a second base sheet 92 facing each other (corresponding to two opposite sheets at the opening of the package), a blocking sheet 93 secured to the second base sheet 92, and fastening units 94, 95 respectively disposed on the first base sheet 91 and the blocking sheet 93. The fastening units 94, 95 respectively disposed on the first base sheet 91 and the blocking sheet 93 are near the opening 90 of the package and configured to be fastened to each other for closing the opening 90 of the package.
In this regard, however, using such surface bonding fastener still cannot solve the problem that the contents contained in the package may drop out of the package when the package is reversely placed due to the possibility that the opening of the package may be opened unintentionally. Specifically, although the blocking sheet 93 secured to the second base sheet 92 can disperse parts of pressure applied to the fastening units 94, 95, which is used to close the opening 90 of the package, from the contents contained in the package, yet if the package is reversely placed for a long time or the weights of the contents contained in the package is heavy, it still cannot prevent the contents contained in the package from opening the fastening units 94, 95 (as shown by arrows in FIG. 2) so as to make the contents drop out of the package, as shown in FIG. 2.
In view of above, since the conventional surface bonding fasteners have the above-mentioned drawbacks, it motivates the inventor of the present invention to research and develop an improved surface bonding fastener that is advantageous with respect to the conventional surface bonding fasteners as previously described.